Process for producing alkylbenzene

Abstract

A process for producing an alkylbenzene from an alkylphenyl alcohol involving the steps of: (a) feeding a feed stream containing alkylphenyl a reactor having a catalytic distillation zone; and, (b) concurrently in the reactor (i) contacting the feed stream containing alkylphenyl alcohol with hydrogen in the catalytic distillation zone to convert alkylphenyl alcohol to alkylbenzene over a catalyst containing Group VIII or a Group IB metal; and, (ii) separating alkylbenzene from the reaction mixture by fractional distillation to produce an overhead stream containing alkylbenzene having a reduced concentration of alkylphenyl alcohol than the feed stream from the distillation column reactor. Examples of the alkylphenyl alcohol include cumyl alcohol, phenyl ethyl alcohol, or di(2-hydroxyl 2-propyl)benzene, and that for the alkylbenzene include cumene and di-ethyl benzene, or di(2-hydroxyl-2-propyl)benzene.

1. A process for producing an alkylbenzene having the structure of R 1 R 2 C(Ph) from an alkylphenyl alcohol having the structure R 1 R 2 C(Ph)OH comprising the steps of:
 (a) feeding a feed stream comprising alkylphenyl alcohol having the structure R 1 R 2 C(Ph)OH to a reactor having a catalytic distillation zone; and, 
 (b) concurrently in the reactor:
 (i) contacting the feed stream comprising R 1 R 2 C(Ph)OH with hydrogen in the catalytic distillation zone to convert R 1 R 2 C(Ph)OH to R 1 R 2 CH(Ph) and form a reaction mixture, and 
 (ii) separating R 1 R 2 CH(Ph) from the reaction mixture by fractional distillation to produce, at a position higher than the catalytic distillation zone, a stream comprising R 1 R 2 CH(Ph) having a lower concentration of R 1 R 2 C(Ph)OH than the feed stream from the reactor at a position higher than the catalytic reaction zone; 
 
 wherein R 1  and R 2  each is hydrogen or a hydrocarbon group having 1–10 carbon atoms and at least one of R 1  and R 2  is not a hydrogen. 
 
     
     
       2. The process of  claim 1 , wherein less than 1.0% by weight of R 1 R 2 C(Ph) OH in the feed stream is converted to R 1 R 2 CH. 
     
     
       3. The process as claimed in  claim 1 , wherein the alkylphenyl alcohol is selected from a group consisting of p-di(2-hydroxyl-2-propyl)benzene, m-di(2-hydroxyl-2-propyl)benzene, o-di(2-hydroxyl-2-propyl)benzene, 4-(2-hydroxy-2-propyl)cumene, 3-(2-hydroxy-2-propyl)cumene, 2-(2-hydroxy-2-propyl)cumene, and mixtures thereof. 
     
     
       4. The process of  claim 1 , wherein the alkylphenyl alcohol is ethylphenyl alcohol. 
     
     
       5. The process of  claim 1 , wherein in step (b), the feed stream is in contact with a catalyst comprising a Group VIII metal or a Group IB metal of the Periodic Table of Elements in the catalytic distillation zone. 
     
     
       6. The process of  claim 1 , wherein in step (b) the feed stream is in contact with a catalyst comprising palladium in the catalytic distillation zone. 
     
     
       7. The process of  claim 1 , wherein in step (b) the feed stream is in contact with a catalyst comprising copper in the catalytic distillation zone. 
     
     
       8. A process for producing cumene from 2-phenyl-2-propanol comprising the steps of:
 (a) feeding a feed stream comprising 2-phenyl-2-propanol to a reactor having a catalytic distillation zone; and, 
 (b) concurrently in the distillation reactor
 (i) contacting the feed stream comprising 2-phenyl-2-propanol with hydrogen in the catalytic distillation zone to convert 2-phenyl-2-propanol to cumene and form a reaction mixture; and, 
 (ii) separating cumene from the reaction mixture from (i) by fractional distillation to produce, at a position higher than the catalytic distillation zone, a stream comprising cumene and having a lower concentration of 2-phenyl-2-propanol than the feed stream. 
 
 
     
     
       9. The process of  claim 8 , wherein less than 0.5% wt of 2-phenyl-2-propanol in the feed stream is converted to i-propylcyclohexane. 
     
     
       10. The process of  claim 8 , wherein less than about 0.05% wt of the cumene produced in step (i) is converted to 2,3-dimethy-2,3-diphenyl butane or 2-methyl-2,4-diphenyl pentane. 
     
     
       11. The process of  claim 8 , wherein in step (b) the feed stream is in the presence of a catalyst comprising a group IB metal or a group VIII metal in the catalytic distillation zone. 
     
     
       12. The process of  claim 8 , wherein in step (b) the feed stream is in contact with a catalyst comprising palladium in the catalytic distillation zone. 
     
     
       13. The process of  claim 8 , wherein in step (b) the feed stream is in contact with a catalyst comprising copper in the catalytic distillation zone. 
     
     
       14. A process for producing cumene from 2-phenyl-2-propanol comprising the steps of:
 a. feeding a feed stream comprising 2-phenyl-2-propanol to a reactor comprising a distillation reaction zone; 
 b. concurrrently in the reactor
 (i) contacting the feed stream comprising 2-phenyl-2-propanol with hydrogen in the presence of a catalyst comprising a group VIII metal or a group IB metal in the distillation reaction zone to convert 2-phenyl-2-propanol in the feed stream to cumene and form a reaction mixture comprising cumene; 
 (ii)separating cumene from the reaction mixture by fractional distillation; and, 
 (iii)withdrawing, at a position higher than the catalytic distillation zone, a stream comprising from about 98%wt to about 99.9% wt of cumene and having a lower concentration of 2-phenyl-2-propanol than the feed stream from the distillation column reactor; 
 
 c. withdrawing from the reactor a bottom stream comprising 2-methyl-2,4-diphenylpentane and dimethyl-2,3-diphenylbutane from a position lower than the catalytic distillation zone; and, 
 d. converting the 2-methyl-2,4-diphenylpentane and dimethyl-2,3-diphenylbutane in the bottom stream from (c) to cumene. 
 
     
     
       15. The process of  claim 14 , wherein in (b) (ii), less than about 0.5% wt of 2-phenyl-2-propanol is converted to i-propylcyclohexane. 
     
     
       16. The process of  claim 14 , wherein less than about 0.05% by weight of the cumene produced in step (b) (i) is converted to 2-methyl-2,4-diphenylpentane and dimethyl-2,3-diphenylbutane. 
     
     
       17. The process of  claim 14 , wherein in step (b)(i) the feed stream is in contact with a catalyst comprising palladium in the distillation reaction zone. 
     
     
       18. The process of  claim 14 , wherein in step (b)(i) the feed stream is in contact with a catalyst comprising copper in the distillation reaction zone.